The invention relates to a method for producing a multilayer body with a carrier ply and a single- or multi-layered decorative ply formed on and/or in the carrier ply, as well as a multilayer body, a security element and a security document.
Optical security elements are often used to make it difficult to copy documents or products, in order to prevent abuse thereof, in particular forgery. Optical security elements are thus used for the security of documents, banknotes, credit and prepaid cards, ID cards, packaging for high-value products and the like. It is known here to use optically variable elements as optical security elements which cannot be duplicated using conventional copying methods. It is also known to equip security elements with a structured metal layer which is formed in the shape of text, a logo or another pattern.
The production of a structured metal layer made of a metal layer applied to the surface for example by sputtering or vapor deposition requires a plurality of processes, in particular if particularly fine structures, which have a high degree of protection against forgery, are to be produced. Thus it is known, for example, to use positive or negative etching or laser ablation to partially demetallize, and thereby structure, a metal layer applied over the whole surface. Alternatively it is possible to apply metal layers to a carrier already in a structured form by means of using evaporation masks.
The more manufacturing steps are provided for the production of the security element, the greater the significance given to the registration or register accuracy of the individual method steps, i.e. the accuracy of the positioning of the individual tools relative to each other during the formation of the security element with respect to features or layers or structures already present on the security element.